Process for the production of a pressed insensitive explosive mixture

ABSTRACT

For the crack-free production of pressed explosive bodies, in particular jet- and projectile-forming pressed explosive bodies the insensitive explosive mixture has TATB deposited directly on the secondary explosive. It may contain small proportions of binders, for example DOA, calcium stearate or Aerosil.

[0001] Process for the production of a pressed insensitive explosive mixture The invention relates to a process for the production of a pressed insensitive explosive mixture in accordance with European patent application EP 1 101 751 A.

[0002] The invention is based on the object of also proposing insensitive high-performance pressed bodies for jet-forming and projectile-forming hollow charges.

[0003] That object is attained in accordance with the characterising features of claim 1. Advantageous developments of the invention are set forth in the appendant claim.

[0004] The process according to the invention provides crack-free pressed bodies.

[0005] The sonochemical synthesis of TATB involves what is referred to as a two-phase reaction, wherein a solution of TCTNB (trichlorotriaminobenzene) in toluene is caused to react with ammonia solution which is immiscible with that solution.

[0006] The activation energy required for that purpose is applied in that case by a strong ultrasonic source which in addition also provides for an extremely great increase in the phase interfaces at which the chemical reaction takes place.

[0007] By virtue of the step of dropping a TCTNB solution into the saturated ammonia solution, those TATB crystals are refined. That provides for a higher degree of wetting in regard to the explosive crystals. That step is a prerequisite for automatic production of the explosive according to the invention.

[0008] The very fine TATB which is produced upon the reaction taking place can be conveniently filtered off, washed and dried, and can then serve for production of the above-mentioned explosive mixtures.

[0009] In an alternative mode of production (direct process), the procedure involved is now as follows.

[0010] Using ultrasound, a suspension of the respective secondary explosive (in the moistened condition as delivered), that is to say RDX, HMX or CL-20, Nitropenta . . . in excess, aqueous, about 30% ammonia solution is produced, and an amount of TCTNB calculated in accordance with the reaction conversion effect, dissolved in toluene, is added by dropping.

[0011] The resulting very fine TATB is now deposited directly in situ on the suspended secondary explosive particles.

[0012] It was further established by laser diffraction measurement procedures that, by virtue of that dropping-in process, in comparison with the conventional dropping-in process, it is possible to achieve a further reduction in the mean particle diameter of the TATB particles, which in turn still further improves the adsorptive capability.

[0013] That adsorption procedure is also enormously promoted by the formation of strong hydrogen bridge bonds between the nitro groups of the secondary explosives and the amino groups of the TATB.

[0014] After conclusion of the reaction the procedure involves filtering off, washing and drying under vacuum.

[0015] The product obtained can be passed directly for further processing.

[0016] The insensitive explosive mixture has TATB deposited directly on the secondary explosive, for the crack-free production of pressed explosive bodies, in particular jet-forming and projectile-forming pressed explosive bodies. They may contain small proportions of binding agents, for example DOA, calcium stearate or Aerosil. 

1. A process for the production of a pressed insensitive explosive mixture in which the binding agent comprises sonochemically produced 1,3,5-triamino-2,4,6-trinitrobenzene (TATB), characterised in that the TATB which is produced by ultrasound from TCTNB is deposited in very fine particle form on the secondary explosive crystals present in the bath.
 2. A process according to claim 1 characterised in that the TATB disposed in the mixer is dropped into a TCTNB solution.
 3. A process according to claim 1 characterised in that the explosive mixture containing TATB is sonochemically produced in the presence of the secondary explosive directly from the preliminary stage TCTNB.
 4. A process according to claim 1 characterised in that there are added to the explosive mixture small proportions of 0.1 to 3% of binder additives such as DOA (plasticiser), calcium stearate, or Aerosil, for controlling the properties of the pressed bodies. 